1. Field of the Invention
The present invention relates to metal resinates, more specifically to resinates prepared from rosin and Monomer, and to the use of such resinates in inks and coatings, particularly inks for gravure printing.
2. Description of the Related Art
The use of rosin as a major component of the reactants used to prepared binders in printing inks is very well known in the art. Such rosin-based inks are used for a wide variety of printing processes, including flexography, gravure printing, letterpress printing, and lithography. Each printing process requires an ink with properties specific for optimal usage of that particular process, where relevant ink properties include viscosity, solvent evaporation, wettability, pigment dispersion, and compatibility with the other materials composing the ink press. In order to be able to use rosin in inks having such a diverse range of necessary performance properties, it is very important to select the appropriate materials that are reacted with the rosin to form the ink binder. See, e.g., Roger F. Burke, “Rosin-based Printing Inks,” Naval Stores, Chapter 19, Pulp Chemicals Association (1989). Examples of rosin-based inks in the art are summarized below.
U.S. Pat. No. 5,708,078 (Bender et al., 1998) discloses a resin and the process of preparation thereof, where said resin is formed from natural resin and/or natural-resin acid, aldehyde and/or aldehyde acetal, polyhydric alcohol, and metal salt. Optionally, said resin may also comprise α,β-unsaturated carboxylic compound, animal- or vegetable-derived fatty acid and/or fatty acid ester, and/or ethylenically unsaturated hydrocarbon resin. Among the objects of said invention are to provide a phenol-free ink composition, and to provide a binder resin imparting high ink gloss on printed material regardless of processing speed.
U.S. Pat. No. 5,698,668 (Bender, 1997) discloses modified natural-resin ester and the process of preparation thereof, wherein said resin ester comprises the reaction product of natural resin and/or natural-resin acid, α,β-unsaturated carboxylic compound, polyoxophenol compound, aldehyde and/or aldehyde acetal, polyhydric alcohol, metal salt, and dicarboxylic compound not ethylenically unsaturated, optionally animal- or vegetable-derived fatty acid and/or fatty acid ester, optionally aromatic vinyl compound, and optionally polymer or oligomer of alkene. Among the objects of said invention are to provide a binder resin suitable for use in gravure printing of illustrations.
U.S. Pat. No. 5,082,497 (LeVine, 1992) discloses printing ink and rosin resinate compositions comprising the reaction product of rosin, α,β-unsaturated carboxylic compound, metal salts of calcium or zinc and a Group I metal, and hydrocarbon solvent. An object of said invention is to provide improved resinates and gravure printing inks with the inclusion of a reactive Group I metal compound.
U.S. Pat. No. 4,301,055 (Schefbauer, 1981) discloses a calcium resinate and a printing ink composition containing said resinate, wherein said resinate comprises the reaction product of calcium hydroxide, rosin, reactive hydrocarbon resin, polyanhydride of α-olefin-maleic anhydride, and optionally non-reactive hydrocarbon resin. Optionally, said rosin is tall oil, wood, gum, polymerized, and/or polycyclopentadiene-tall oil rosin. An object of said invention is to provide a high melting calcium resinate that will be soluble in hydrocarbon solvents typically employed in printing inks.
U.S. Pat. No. 4,244,866 (Schefbauer, 1981) discloses a printing ink comprising a resinate in a hydrocarbon solvent and a method of resinate preparation thereof, said resinate comprising the reaction product of rosin, calcium hydroxide, and polycarboxylic acid derived from maleic anhydride/α-olefin copolymer. Optionally, the rosin used in the preparation of said binder is tall oil rosin. An object of said invention is to provide a high melting calcium resinate that will be soluble in hydrocarbon solvents typically employed in printing inks.
U.S. Pat. No. 4,079,102 (Wagner et al., 1978) discloses a printing ink composition comprising a binder comprising the reaction product of cycloaliphatic diene resin and olefinically unsaturated polycarboxylic acid, optionally an olefinically unsaturated monocarboxylic acid component selected from C3-12 monocarboxylic acid and functional derivatives of said monocarboxylic acid, optionally a monohydric or polyhydric phenol component, and optionally a metal salt derived from a metal of Groups I-III of the Periodic Table. An object of said invention is to provide a binding agent suitable for use in gravure printing.